Electric heating apparatus



July 9, 1929- y l 4.1. L. HARVY A l 1.720.416

ELECTRIC HEATING APPARATUS Filed May 51. 1927, 2 sheets-sheet 1 lili, I is El l l.; M M

l/a-M EMQ? J. L. HARVEY July 9, 19.29.

nLEc'rnI HEATING APPARATUS 2 Sheets-Sheet 2 Filed lay l, 1927 Klv .NCQXNJ Patented July 9, 1929.

UNITEDSTATES PATENT OFFICE..

JoHN I.. HARVEY, oF MILWAUKEE, WISCONSIN, AssIGNoR 'ro CHAIN :BELT COMPANY,

or mrLwAuxnn, WISCONSIN, A CoRrcRATIoN or WISCONSIN.

`:ELECTRIC HEATING-'APPARATUS i f `Application mea may 31,

V'atory to subjecting them to die action, 4whereby they are headed to form the connecting pins of conveyer chains and the like. A further object of the invention is to provide an electric heater of the class described l having readily adjustable means whereby the length of the portion of the rod which is to be heated may be readily controlled.

, A still further object of the invention is to.

l provide an induction heater of the class devscribed having readily removable watercooled jaws or electrodes and having means whereby Wear of said electrodes may be read ily and quickly compensated.

`A still further object of the invention is toV provide a heater of the class described which will be simple in construction, comparatively inexpensive to' manufacture and install and more efficient in use than those. which have been heretofore proposed.

With the above` and other objects in View` which will appear as the description proceeds, the invention consists in thenovel details of construction, and combinations of parts more fully hereinafter described, and particularly pointed out in the appended claims. Y

Referring to the accompanying drawings forming apart of this specification in which like reference characters designate like parts in `all the views: Y

Figure 1 is a side elevational view Vof a heater constructed in accordance with the present invention;

Fig. 2 is a top 4plan view ofthe jaws or electrodes and their associated parts; j

Fig. 3 is a longitudinal vertical sectional view taken approximately on the plane indicated by the line 3-3 of Fig. 2;` and,

Fig. 4 is a wiring diagram illustratingthe` y through which chamber, cooling water or 1927. Serial 195,435.

other fluidvis adapted yto be passed by means of pipes 20 and 21. f

inasmuch as the jaw structure carries the heatmg current, a sheet of insulating material 22 is preferably interposed between thecool-p ing chamber' 18 and the bracket 16 to insulat the frame from the jaw. l

Detachably secured to the coolingchamber 18 by bolts 23 is the copper electrode 24 which is provided with asubstantially semicylindrical recess or groove 25.

Coacting with the stationary electrodev 17 is -a Vmovable electrode .structure indicated generally by the .numeral 26, the construction of which will now be described. Y

y Rigidly secured to thevhorizontal member 12, as by the bolts 27 is a hollowcylindrical bearingfblock-or member 28 provided at one end with al removable head 29 intowhich is threaded an adjustable. plug 30, aswill be clear from Figs. 2 and 3. A plunger '31, is slidably mounted in` the bearing block 28 and is prevented from.v rotating therein Vby means of a key 32. Sai-d plungeris holloWed out as at 33 to receive a coil spring 34,'one end of which seats against'the bottom 35 of the bore 33 while the other ends seats against the material- 38 being interposed between they plunger 31- and the'cooling chamber 37, as

will be readily understood. Cooling water is, conducted to and fromthe cooling chamberl 37 throuo'hthe pipes39. and 40 and the said cooling hamber has detachably secured to it as by the vbolts 41, acopper jaw 42 which is a duplicate of the jaw 24 and which is' provided with .the substantially semi-cy-y lindrical recess or groove 43. V The plunger 31 has threaded into itas at 45, one endfof` an axial rod 46 which rod passes through a. bore 47 provided inthe threaded plug 30 and terminates atthe bifurcated connecting member 48 through which it is connected to a lever 49 pivoted as at450 in a Vbracket 51 carried by the frame work 10.A A

pin and slot connection 52 provides the necessary lost motion to compensate between the arcuate movement of the lever. 49 and the straight line movement of the rod 46, as will be readily understood. The said rod 46 is threaded as at 59 and carries a pair of lock 60 i from the foregoing'but it may be briefly sum- Y pearmore fully below. I

nuts 58 which serve as stops to limit the forward .travel of the movabler electrode, as will appear more fully below.

, The lever 49 has pivotally secured toit, as

at 53, a rod or link 54 which is provided with a turn buckle 55 by means of which the length of the said link 54 may be adjusted. The link 54 is pivotally connected'` as at 56 to a :toot leverl 57 by means of which the movable A electrode is moved in one direction as will ap- As above stated, the copper 24 and 42 are duplicateswhereby they areinterchange'- able and their semi-cylindrical recesses orA grooves 25,'and 43 are aligned to form la substantially cylindrical pinreceiving recess.

In order to control the length of the portion of the pin o r rod which is to be heated, there is provided within this recess, a set screw 60 which is threaded into the horizontal member v 13, and which is adjustable up and down, as

will bereadilylunderstood,to act as a stop to contlolthe length of the portion ot the pin receivedbctween the jaws 24 and 42. In other words, by lowering the'screw 60, a longer portion of the pin is receivable between the jaws,

while by raising the screw 60, a shorter portion.v of the pin will be received between the jaws and heated.v As shown invFig. 3 the stop screw is smaller-in diameter than the recess.V formed byA the two semi-cylindrical grooves. 25 and 43 of the rjaws 24 and 42 respectively, so that. when a rivet or pin is gripped between the said jaws the latter do notycontact with the stop screw which consequently is not included in the heating circuit.

Thestationary and movable electrodes 17 and-26 are provided with suitable brackets 6l and 62 respectively,fwhich carry the. secondary Vcoils ofgthe: electricaltransformer 63. which is mounted within theframe l0. The ends o'lthe secondary winding 65, as lwill be clear from the'wiring diagram shown in Figure 4, are connected respectively to the jaws 24 and 42 while the primary winding 66 of the said transformer is tapped at a plurality of pointsthroughout its length, the said taps 67 leadingto contacts 68 which are adapted to be engaged by a suitable switch handle 69 whereby 'the eliective length of the primary -f 4may be controlled` and-in this manner. the induced current inthe secondary may likewise be controlledf .In actual'use upon a twov hun'- dred and twenty volt single phase, sixty cycle circuit, the .amper-age Y in the primary may range from forty to seventy-iive'while that in only necessary to depress the foot lever 57 which,` through the link 54 and rockinglever A49r will exert a pull on the rod 46 and through it upon the plunger 3l. This pull will move the electrode 26' toward the left as viewed `inl Figs. 2 and 3 against the'pressure of the spring 3.4thereby separating the jaws 42 and 24`suficiently to' permit the rod or pin to be inserted l between gthem. The distance to which the said rod or pin is inserted will be governed by the position of thestop screw v60 l and upon the release of the foot lever 57, the movable electro de will be returned toward the right as viewed in said. figures by the spring- 34, whereby the jaws 42Yand 24will be caused '80 to grip .the rod. Current now being passed through theprimary of the transformer, the induced current set up inthe secondary thereof, will pass through the portion of the pin between .the jaws` 42 and 24, thereby heating such portion, as will l-be readilyunderstood. When the desired temperature has been reached, the loot lever 5,7 is` again depressed to release the pin which is withdrawn and placed in suitable dies to lorml the head thereon.

VIt desired, an automatic switch 70 may be Y employed which is actuated by the lootlever 57 so that when the latter is released the primary 4circuit will be automaticallyfclosed to immediately start the heating and when the lever is depressed the circuit will bebroken to out eff' the current and stop the heating.

The pressure exerted by the spring 34 to move the electrode 26 toward thegright,l as viewed in the drawings, may be controlled by adjusting` the/threaded plug 30,as 1 will be readily understood.` Likewise, if the jaws 24 and 42 become worn, suchwear` may be compensated `for through adjustment. of, the turn buckle 65 *andI the stop nuts 58 Vupon the threaded portion 59 of ythe rod 46. Y

Whileone form of the invention has been thus illustrated and described, -it isobvious that those skilled in the artmay vary the details-of construction aswell as the precise arrangements of partswithout departing from thespirit of the invention and therefore, it is not wished to be limited tothe .above disclosure except Las may be required by the claims. .-1 'n i What is claimed is: p

l. In an electric heater of-the yclass described, a pair of electrodes having recesses adapted to receive the work to be heated; and an adjustable stop member for determining the proportion of said work received between said electrodes, said stop memberbeing positioned between said electrodes within said recesses and being of smaller dimens-ions than said recesses, whereby it will remain out of contact with said electrodes.

2. An electrode structure for electric heaters comprisinga support; and a cooling'chamber yprovided with a.v work-engaging jaw secured to and insulated from saidy support,

said cooling chamber and aw being adapted to be included in the heating circuit of the heater. Y y

3. An electrode structure for electric heaters, comprising a support; a cooling chamber detachably secured to and insulated from ,said support; and a readily detachable jaw car ried by said chamber.

4. In an electric heater of the class described, a frame; a stationary electrode mounted on said frame; a bearing block mounted on said frame in spaced relation to said electrode; a plunger slidably mounted in said block; a movable electrode carried by said plunger; a spring normally urging said plunger and movable electrode toward said stationary electrode; and means for moving said plunger and movable electrode away from said stationary electrode.

5. In an electric heater of the class described, a frame, a stationary electrode mounted on said frame; a bearing block mounted on said frame in spaced relation to said stationary electrode; a plunger slidably mounted in said block; a movable electrode carried by said plunger; a plug threaded in said bearing block; a spring interposed between said plug and said plunger, normally urging said plunger and movable electrode toward said stationary electrode; and means for moving said plunger and movable electrode away from said stationary electrode.

6. In an electric heater of the class described, a frame; a stationary electrode mounted on said frame; a bearing, block mounted on said frame in spaced relation to said stationary electrode; a plunger slidably mounted in said block; a movable electrode carried by said plunger; a spring normally urging said plunger and movable electrode toward said stationary electrode; a rod connected to said plunger; means carried by said rod for limiting the movement of said movable electrode toward said stationary electrode; and means connected to said rod for moving said plunger and movableV electrode away from said stationary electrode.

7. In an electric heater of the class described, a frame; a stationary electrode mounted on said frame; a bearing block mounted on said frame in spaced relation to said stationary electrode; a plunger slidably mounted in said block; a movable electrode carried by said plunger; a spring normally urging said plunger and movable electrode toward said stationary electrode; a rod connected lto said plunger; means carried by said rod. for limiting` the movement of said movable electrode toward said stationary electrode; and means connected to said rod including a loot lever and an adjustable link for moving said plunger and movable electrode'avvay from said stationary electrode.

JOHN L. HARVEY. 

